Complete disassembly, inspection, cleaning, and rebuild of the Delco-Remy distributor on a 1966 Corvette 327 V8, including point replacement, condenser replacement, and timing reset.

Warnings

Tools required

Parts

• Ignition point set × 1 — Delco D104 or equivalent
• Condenser × 1 — Delco D101 or equivalent
• Distributor cap × 1 — Use OEM specification for 8-cylinder
• Rotor × 1 — Delco 1875048 or equivalent
• Distributor cam lubricant × 1 — High-temp distributor grease
• Distributor base gasket (if equipped) × 1 — Use OEM specification
• Vacuum advance diaphragm (if defective) × 1 — Use OEM specification

Preparation

1. Disconnect negative battery cable.
2. Allow engine to cool completely if recently run.
3. Verify engine is at normal operating temperature for initial timing reference (if setting baseline timing before removal).
4. Gather all replacement parts and inspect for correct application before disassembly.
5. Clean the area around the distributor base to prevent debris from entering the engine when distributor is removed.

Procedure

1. 1

   Mark distributor position and timing reference
   Use a scribe or paint marker to mark the distributor body position relative to the intake manifold. Note the position of the vacuum advance canister for reference. Use a timing light to verify and record current timing setting (should be approximately 4-8 degrees BTDC at idle for stock 327). Mark the rotor position relative to the distributor body so you know where it points when reinstalled.
2. 2

   Disconnect distributor electrical connections
   Label and disconnect the primary wire connection from the coil to the distributor (small wire on the negative coil terminal). Disconnect the vacuum advance hose from the vacuum advance canister on the distributor body. Remove the distributor cap by releasing the two retaining clips, and carefully move the cap with plug wires attached out of the way.
3. 3

   Remove distributor from engine
   Using a 9/16" wrench or distributor wrench, loosen the distributor hold-down clamp bolt at the base of the distributor. Do not fully remove the bolt unless necessary. Carefully pull the distributor straight up and out of the intake manifold. Note the rotor will rotate slightly as the drive gear disengages from the camshaft; mark this final resting position for reassembly reference.
4. 4

   Disassemble distributor cap and rotor
   Inspect the distributor cap for cracks, carbon tracking, or burned terminals; replace if defective. Remove the rotor by pulling straight up (press-fit) or removing the two screws (depending on rotor type). Inspect rotor tip for burning or erosion.
5. 5

   Remove breaker points and condenser
   Remove the single screw securing the condenser wire and primary wire to the breaker point terminal post. Remove the condenser mounting screw and remove the condenser from the breaker plate. Remove the two screws securing the breaker point set to the breaker plate and lift out the point assembly. On dual-point distributors, repeat for the second point set.
6. 6

   Clean and inspect distributor components
   Use contact cleaner to spray out the distributor housing, breaker plate, and all pivot points. Inspect the distributor shaft for excessive play (more than 0.006" radial movement indicates worn bushings). Inspect the breaker cam lobes on the shaft for wear or flat spots. Check the vacuum advance diaphragm by applying vacuum manually; it should hold vacuum without leaking and the breaker plate should move smoothly.
7. 7

   Install new condenser
   Mount the new condenser to the breaker plate using the original mounting screw. Position the condenser wire lead so it will reach the breaker point terminal without strain. Snug the mounting screw but do not overtighten (approximately 15-20 inch-lbs).
8. 8

   Install new breaker point set
   Apply a small amount of distributor cam lubricant to the breaker cam lobes on the distributor shaft (use the lubricant stick provided with point set or high-temp grease). Position the new breaker point set on the breaker plate, aligning the mounting holes. Install the two mounting screws and snug them finger-tight. Connect the condenser wire and primary wire to the breaker point terminal post and secure with the terminal screw.
9. 9

   Set breaker point gap
   Rotate the distributor shaft by hand until the rubbing block of the breaker points rests on the highest point of one cam lobe (points fully open). Insert a 0.019" feeler gauge between the point contacts. Loosen the point set mounting screws slightly and adjust the eccentric adjustment screw or point position until the 0.019" gauge has light drag when pulled through the gap. Tighten the mounting screws and recheck the gap; readjust if necessary. The factory specification for 1966 327 V8 single-point distributors should be verified against the service manual (commonly ~0.019" gap / ~30 degrees dwell); set by dwell meter when possible.
10. 10

    Verify point spring tension and alignment
    Visually confirm that the point contacts align properly when closed (full contact across both surfaces, not edge contact). Check that the point spring provides firm closing action. If points misalign or spring tension is weak, replace the point set.
11. 11

    Reinstall rotor and inspect distributor cap
    Install the new or inspected rotor onto the distributor shaft, ensuring it is fully seated. If using a screw-type rotor, install the two retaining screws. Inspect the new distributor cap terminals for proper contact depth and ensure the center carbon button moves freely.
12. 12

    Reinstall distributor into engine
    Rotate the distributor shaft so the rotor points to the position you marked during disassembly (accounting for the counterclockwise rotation that will occur as the drive gear engages). Insert the distributor into the intake manifold, meshing the drive gear with the camshaft helical gear and engaging the lower tang into the oil pump driveshaft slot. The rotor should rotate slightly and end up pointing at your marked position. Align the distributor body with your scribed reference marks. Install and snug the hold-down clamp bolt finger-tight, leaving the distributor loose enough to rotate for timing adjustment.
13. 13

    Reconnect electrical connections
    Install the distributor cap and secure with the two retaining clips. Reconnect the primary wire from the coil negative terminal to the distributor. Reconnect the vacuum advance hose to the vacuum advance canister.
14. 14

    Set initial timing
    Reconnect the battery negative cable. Start the engine and allow it to reach normal idle (approximately 600-700 RPM in neutral with the parking brake set). Disconnect and plug the vacuum advance hose at the carburetor. Connect a timing light to the number 1 cylinder spark plug wire. Aim the timing light at the timing tab on the front cover. Loosen the distributor hold-down clamp and rotate the distributor body until the timing mark on the harmonic balancer aligns with the specified timing mark (verify factory spec for your specific engine — approximately 4 degrees BTDC for base L75, higher for L79, at idle with vacuum advance disconnected). Tighten the hold-down clamp bolt to secure the distributor.
15. 15

    Verify and finalize timing
    Recheck timing with the timing light to confirm the setting did not shift when tightening the hold-down clamp. Reconnect the vacuum advance hose and verify that timing advances smoothly when engine RPM is increased. Confirm idle quality is smooth and engine accelerates cleanly without hesitation.

Reassembly

1. Ensure all electrical connections are secure and spark plug wires are fully seated in distributor cap towers.
2. Double-check that the distributor hold-down clamp is tight and the distributor cannot rotate.
3. Verify vacuum advance hose is connected and not cracked or leaking.
4. Confirm battery negative cable is securely reconnected.

Verification

• Start the engine and listen for smooth idle with no misfires or rough running.
• Use a timing light to verify initial timing is set to specification (4-8 degrees BTDC for stock 327 V8).
• Rev the engine and confirm timing advances smoothly with vacuum advance connected.
• Test drive the vehicle to verify smooth acceleration and no hesitation under load.
• Re-verify timing after the first 50-100 miles as components settle.

More procedures for this vehicle